Method, system, and program for performing workflow related operations using an application programming interface

ABSTRACT

Provided is a method, system, and program for performing workflow related operations. An application programming interface call (API) is received to perform a workflow related operation. A determination is made of at least one stored procedure call associated with the received API. The determined at least one stored procedure is then called to cause the execution of one determined stored procedure on a database server to perform the workflow related operation of the API.

RELATED APPLICATIONS

This application is related to the following copending and commonlyassigned patent applications, which are incorporated herein by referencein their entirety:

“Method, System, and Program for Generating a Workflow”, havingapplication Ser. No. 09/894,074, and filed on Jun. 28, 2001;

“Method, System, and Program for Using Objects In Data Stores DuringExecution of a Workflow”, having application Ser. No. 09/894,413, andfiled on Jun. 28, 2001;

“Method, System, and Program for Executing a Workflow”, havingapplication Ser. No. 09/894,076, and filed on Jun. 28, 2001;

“Method, System, and Program for Maintaining Information in DatabaseTables and Performing Operations on Data in the Database Tables”, havingapplication Ser. No. 09/09918144, and filed on the same date hereof.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method, system, and program forperforming workflow related operations.

2. Description of the Related Art

A workflow program allows businesses and other organizations to definetheir business operations as a computer model known as a workflow. Aworkflow defines a series of processes to be performed by users at aclient computer. The user activities at the client computers may involveupdating an electronic form, reviewing information, etc. After one userin the workflow performs a specified action, the work item or otherinformation is then routed to one or more further nodes where furtheraction may be taken. For instance, an on-line purchase of a product mayinvolve numerous steps, such as receiving the customer order, routingthe customer order to the credit department to process the bill and thenrouting the order to the shipment department to prepare the shipment.Once the shipment is prepared, the product may be shipped andinformation on the purchase is then transferred to the customer servicedepartment to take any further action. Each of these processes may bedefined as nodes in a workflow. A workflow program would then route thecustomer order to the business agents designated to handle the job. Forinstance, the initial order would be received by the order departmentand then routed to a person in shipping and billing. Once the bill andpackage are prepared, a further invoice may be forwarded to shipping.After shipping sends the package, the shipping agent may then enterinformation into the invoice and forward the electronic invoice tocustomer service for any follow up action.

A workflow is designed using workflow software, such as theInternational Business Machines Corporation (IBM) MQSeries** Workflowsoftware product. A process modeler is a person that analyzes thebusiness operations, determines how the information related to theoperations is routed electronically to client computers, and thendefines a workflow model of the operations. The workflow model may becoded in the FlowMark Definition Language (FDL). The workflow model isthen imported into a Runtime program that verifies and translates theworkflow model into a process template. An instance of the processtemplate can then be invoked to automates the sequence of events definedby the model. **MQSeries, IBM, and DB2 are registered trademarks ofInternational Business Machines Corp.; Microsoft and Microsoft SQLServer are trademarks of Microsoft Corporation; ORACLE is a trademark ofthe Oracle Corporation; Java is a trademark of Sun Microsystems, Inc.

Current workflow programs provide an application program interface (API)for client applications to use to interact with the workflow engine andperform workflow related functions and operations. In prior artimplementations where the API is implemented in Java**, a Java NativeInterface (JNI) wrapper is provided to translate the Java APIs to thenative code of the workflow engine. The workflow engine then executesthe native code to perform the function specified by the API. Inaddition, a database is usually provided to store workflow relatedinformation and metadata. Java APIs are also provided to access workflowmetadata in the workflow database. Thus, the client program would issueJava APIs to interact with the workflow engine and separately call otherAPIs to interact with the workflow database to access and manipulateworkflow metadata. **MQSeries, IBM, and DB2 are registered trademarks ofInternational Business Machines Corp.; Microsoft and Microsoft SQLServer are trademarks of Microsoft Corporation; ORACLE is a trademark ofthe Oracle Corporation; Java is a trademark of Sun Microsystems, Inc.

The programming of the JNI interface are very difficult and cumbersometo code and debug. Further, the JNI interface developed for one vendorworkflow engine is not reusable because it is closely coupled with thespecific workflow engine implementation and cannot be reused with othervendor workflow engine implementations. In fact, the software developerwould have to recompile every JNI interface based on the compiler andclient/server architecture used for different vendor workflow engines.

For these reasons, there is a need in the art to provide improveddesigns of workflow programs.

SUMMARY OF THE PREFERRED EMBODIMENTS

Provided is a method, system, and program for performing workflowrelated operations. An application programming interface (API) call isreceived to perform a workflow related operation. A determination ismade of at least one stored procedure call associated with the receivedAPI. The determined at least one stored procedure is then called tocause the execution of one determined stored procedure on a databaseserver to perform the workflow related operation of an API of the APIcall.

In further implementations, at least one stored procedure call invokesone stored procedure in the database server that includes nativeworkflow server code to communicate to a workflow server to execute toperform the workflow related operation of the API and at least onestored procedure call invokes one stored procedure in the databaseserver that includes database statements executed by a database programto access workflow related metadata for the API.

Further provided is a method, system, and program for performingworkflow related operations at a database server in communication with aclient. At least one call to one stored procedure is received at thedatabase server associated with an application programming interface(API) call invoked from the client to perform a workflow relatedoperation. The database server executes the at least one called storedprocedure to perform the workflow related operation of an API of the APIcall.

In still further implementations, at least one call to one storedprocedure comprises a first and second stored procedure calls to firstand second stored procedures, respectively, on the database server toimplement the workflow related operation of the called API.

The described implementations provide a workflow design in aclient/server environment that utilizes stored procedures on a databaseserver to perform the workflow related operations associated with aworkflow related API. The stored procedures may include native workflowserver code to send to the workflow server to perform the workflowrelated operations specified by the API and/or access workflow metadatain a workflow database.

BRIEF DESCRIPTION OF THE DRAWINGS

Referring now to the drawings in which like reference numbers representcorresponding parts throughout:

FIG. 1 illustrates a workflow computing environment in which aspects ofthe invention are implemented;

FIG. 2 illustrates logic performed by a workflow server to execute aworkflow in accordance with implementations of the invention;

FIG. 3 illustrates an architecture of object oriented classes forimplementing a workflow in accordance with implementations of theinvention;

FIGS. 4 and 5 illustrate logic to utilize the methods and objects fromthe object oriented class architecture of FIG. 3 to execute a workflowin accordance with implementations of the invention;

FIG. 6 illustrates an architecture of a workflow computing environmentin accordance with implementations of the invention; and

FIGS. 7 and 8 illustrate logic implemented in the architecture of FIG. 6to perform workflow related operations in accordance withimplementations of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following description, reference is made to the accompanyingdrawings which form a part hereof and which illustrate severalembodiments of the present invention. It is understood that otherembodiments may be utilized and structural and operational changes maybe made without departing from the scope of the present invention.

FIG. 1 illustrates a workflow environment implementation in which theinvention is realized. A workflow engine 2 includes a runtime database 4and a workflow server 6, such as the IBM MQSeries Workflow server. Theworkflow server 6 is capable of transforming a workflow model coded in aworkflow definition language (WDL) file 10, such as FDL, into a processtemplate 8 implemented in the runtime database 4. The runtime database 4stores database tables that implement the data structures that providethe status and setup information needed for workflow process execution.Whenever the state of a process activity changes, such information isrecorded in the runtime database 4. The runtime database 4 may beimplemented using any database program known in the art, such as IBMDB2.** **MQSeries, IBM, and DB2 are registered trademarks ofInternational Business Machines Corp.; Microsoft and Microsoft SQLServer are trademarks of Microsoft Corporation; ORACLE is a trademark ofthe Oracle Corporation; Java is a trademark of Sun Microsystems, Inc.

The workflow server 6 coordinates and manages the execution of processesfor a defined process template 8. The workflow server 6 executes anyprograms associated with a process defined for the workflow, interpretsthe process definitions, creates process instances and manages theirexecution, manages processes and states, logs events, communicates withusers as part of the workflow, etc. The workflow server 6 may include adatabase client program (not shown) to access and update records relatedto the workflow being processed maintained in the runtime database 4.The workflow server 6 processing may be distributed across multiplecomputers to achieve workload balancing.

The workflow clients 12 a, b . . . n represent the client computers thatexecute workflow application program interfaces (APIs) to performworkflow related actions and activities and return messages to theworkflow server 6. The workflow clients 12 a, b . . . n thus compriseinstances of the workflow code on the client computers that allow usersto interface with the executing workflow and the workflow server 6. Theworkflow server 6 would execute activity programs as part of executingthe workflow and transmit messages and data to the workflow client 12 torequest user action to proceed with the workflow. The actions associatedwith the nodes and executed by the workflow server 6 may comprise Javaservlets. The workflow client 12 may comprise a Web browser capable ofexecuting Java scripts transferred from the Java servlet executing onthe workflow server 6. Further, details on implementations andinteractions of the workflow server 6 and client 12 are described in theIBM publication “IBM MQSeries Workflow: Concepts and Architecture,Version 3.3”, IBM document no. GH12-6285-03 (March, 2001), whichpublication is incorporated herein by reference in its entirety.

A workflow builder 20 comprises a system including a buildtime program22 that implements a plurality of graphical user interface (GUI) panelsin which a user may define the components of a workflow model 24. Aworkflow translator 26 converts the workflow model 24, with the definedworkflow components, into a workflow definition language (WDL) file 10that implements the workflow model 24. The workflow definition language(WDL) may comprise the FlowMark Definition Language (FDL), WorkflowProcess Definition Language (WPDL) or any other workflow definitionlanguage known in the art that is used to define workflows. The workflowtranslator 24 would transfer the WDL file 10 to the workflow server 6 totransform into a process template 8 in the runtime database 4 in amanner known in the art. Further details of using the buildtime program22 to build workflows are described in the copending and commonlyassigned patent application “Method, System, and Program for Generatinga Workflow”, having application Ser. No. 09/894,071, which applicationwas incorporated herein by reference above.

The workflow engine 2, and each of the program components therein, suchas the runtime database 4 and workflow server 6, may be implemented inone or more computing machines. The workflow clients 12 which providethe workflow interface to users may be implemented on one or more clientmachines. The workflow builder 20, including the buildtime program 22and workflow translator 26 programs, may be implemented on one or morecomputing machines. Any portion of the workflow engine 2, workflowbuilder 20, and/or workflow client 12, and program components therein,may be implemented on the same computing machines or separate machines.The computing machines used to implement the workflow engine 2, workflowclients 12, and workflow builder 20 may comprise any computing deviceknown in the art, such as a server, workstation, mainframe, personalcomputer, laptop computer, hand held computer, telephony device, etc.

One use of a workflow is to generate a final product, which may comprisethe result of the effort of a single business unit or the cumulativeefforts of multiple users and units within an organization. To producethe final product, a workflow packet comprised of one or more documentswould transfer through various user work stations in the company definedas nodes in the workflow to require the user associated with such nodeto handle and process and forward to another user to handle. A documentis comprised of a multimedia item that has digital content.

For instance, an insurance company may have to process numerousdocuments related to an insurance claim, such as photographs,appraisals, expert reports, etc. Employees may spend a substantialamount of time sorting through documents and associating the documentswith particular claims. In the workflow model, all the documents relatedto a single claim would be part of a work packet that may move throughvarious user stations to review and process. The workflow would comprisethe flow of work and actions that are performed on the documents orworkflow packet by multiple users in the system.

The workflow defines the sequence and boundaries of how the work isperformed with respect to the documents in the workflow packet, and anyrestrictions on the order in which documents in the workflow packet mustbe processed. For instance, before the claim can proceed to a furtherstep, a claims adjuster might be required to ensure that certaindocuments are included in the workflow packet for the claim before theworkflow packet can proceed to further nodes in the workflow, e.g.,determining the amount of compensation.

In workflow terminology, a worklist is a queue of work items. Each workitem comprises a unit of work for a node in the workflow that isperformed by the users associated with that node. Each work item may beassociated with one work packet, which comprises documents or objectsthat are processed during the work defined for that work item. When auser at one node accesses the work item to perform the work definedtherein, that work item is locked, thereby preventing others at thatnode from accessing the work item.

A worklist, which is a queue of work for the users of the organizationto perform with respect to the workflow packet. The work items withinthe worklist can be handled by any of the employees/users assigned tothe worklist. An action list defines the actions that a user can performon the work packet objects associated with the work item, such asselections or data that may be entered in the work packet. For example,an adjuster in the claim process workflow can select an option tocontinue consideration of the claim if it appears valid or select anoption to reject the claim. The workflow further consists of the pathsdefined as the connections between nodes which indicate the order ofexecution of nodes in the workflow.

An action list may be associated with a workflow that provides a listthe actions that can be invoked at the nodes in the defined workflow.The actions may comprise programs that are executed at a particularnode. In certain implementations, the actions comprise Java methods thatthe workflow server 6 executes when control proceeds to the node withwhich the method is associated. Action in the list would be associatedwith particular nodes. An access list defines a mapping of users thatcan be assigned to nodes to perform the action associated with suchnode. An notification feature causes a message to be sent to a specifieduser if the user associated with a node has not performed the actiondefined for the node within a specified time frame.

One or more actions and a user with are associated with the work nodesin the workflow. The work nodes defined for the workflow may comprise adecision point node, collection point node, document node, and assignvalue node. A decision point node causes the workflow to proceed along abranch of execution based on selection by the user or some other actiontaken by an external application called at a previous work node. Forinstance, the path taken to the next node in the workflow may vary ifthe claim adjuster selects to reject the claim as opposed to approvingthe claim. A collection point node is a work node where certaindocumentation is gathered and added to the work packet. The collectionnode holds and manages work packages that cannot be processed completelyuntil additional information is received. A document node represents adocument in the workflow.

In certain implementations, the workflow model 24 defined using thebuildtime program 22 is document centric in that the actions performedat the node concern the processing of work packages that may compriseany content or object that is processed and routed through the workflow.FIG. 2 illustrates the logic performed by the workflow server 6 toexecute a workflow. When a user invokes a workflow stored in the runtimedatabase 4, the workflow server 6 accesses (at block 100) the start nodeof the invoked workflow by interacting with the runtime database 4 in amanner known in the art. From the properties defined for that node, theworkflow server 6 determines (at block 102) the actions and userassociated with the node. The workflow server 6 further processes (atblock 104) the access list defined for the workflow to determine thework item for the accessed node. If (at block 106) the determined workitem currently accessed in the workflow is locked by another user atthat node, then the workflow server 6 waits (at block 108) for the lockon the work item(s) to be released. If the work item is not locked orafter the lock is released, control proceeds to block 110 where theworkflow server 6 places a lock on the determined work item. Theworkflow server 6 then executes (at block 112) the action associatedwith the node and communicates data to the workflow client 12 of thedetermined user requesting user action.

If (at block 114) notification is enabled for the current node and thedeadline has passed (at block 116) without receiving a response from theuser, then the workflow server 6 notifies the user specified with theenable notification that the deadline has passed. Upon receiving (atblock 118) a response from the user, which may comprise enteringinformation, modifing a work item, adding a work item to the workpackage, selecting an option, etc., the workflow server 6 unlocks (atblock 120) the work item(s) previously locked for the user. If (at block122) the current node is the stop node, then control ends; otherwise, ifthere are further nodes to process in the workflow, then the workflowserver 6 determines (at block 124) from the path from the current nodethe next node in the workflow and accesses (at block 126) the next node.Control then proceeds back to block 326 to process the next node.

The workflow logic of FIG. 2 provides a document centric workflow inthat the state of processing work items associated with the nodecontrols the workflow because control cannot proceed to other subsequentnodes that process the locked work item until the node holding the lockcompletes execution and releases the lock on the work item. Thus, accessto work items controls the flow through the workflow.

With the described implementations, the workflow builder 20 generates aWDL file 10 that may be compatible with workflow engines from differentvendors because different vendors may design their workflow engines tobe compatible with the WDL format of the WDL file 10. This allows theworkflow model defined in the WDL file 10 to be transportable acrossdifferent vendor workflow engine platforms.

Object Oriented Workflow Architecture

FIG. 3 illustrates an architecture of object oriented classes and theirinterrelationship that are used to implement a workflow of nodes. Asindicated in the legend 400, a rectangle indicates a class; a lineconnecting classes indicates an association of the connected classes; aline connecting classes terminating in a filled circle indicates thatthere may be one or more instances of the class at the end with thecircle for each instance of the class at the other end of the line; anda line terminating at a diamond indicates that the class at the diamondend is an aggregate, such that the aggregate object is made up of one ormore instances of the class at the other end of the line. FIG. 3illustrates the relationship of the classes.

The WorkFlowService class 402 is the starting point for a user wantingto access a workflow. The WorkFlowService class 402 includes methodsthat allow users to access already defined workflow templates andexecuting workflows. The WorkFlowService class 402 is associated withthe WorkFlowTemplate 404, WorkFlow 406, and WorkFlowList 408 classes.The WorkFlowTemplate class 404 provides methods that allow the user tomanipulate workflow process template objects, e.g., process template 8(FIG. 1), which comprise a defined workflow that is stored in theworkflow engine 2. The WorkFlow class 406 provides methods that allowthe user to access information and control an executing workflow. TheWorkList class 408 includes methods that allow the user to access anexecuting work list object comprised of work items and information onthe current state of the executing work list, i.e., information on workitems being processed. The methods in the WorkFlowService class 402 areused to retrieve information on particular workflows, workflowtemplates, and workflow lists associated with a particular workflowservice. The methods from the other classes, such as theWorkFlowTemplate 404, WorkFlow 406, and WorkFlowList 408 classes, canthen be used to obtain specific information and control over thoseworkflow templates, workflows, and workflow lists identified by theWorkFlowService class 402 methods.

The WorkFlowTemplate class 404 provides information on a workflowtemplate. A workflow object from the WorkFlow class 406 represents anexecuting workflow. The WorkFlowContainer class 410 includes methods toinstantiate a container object that includes information on onecontainer used to transfer data between nodes. Users at nodes may accessdata in the container and update the container with additional data. Thedata in the container may be used by the action being executed at anode. The WorkFlow class 406 is associated with the WorkFlowNotificationclass 412, which is used to provide notifications, such as notificationsif a user does not perform an action at a node within a predefined timeperiod. There may be many notifications provided for one workflow. TheWorkFlow class 406 is further associated with the WorkFlowItem class414, such that one executing workflow may be associated with one or morework items indicating a unit of work to perform for a node within theworkflow. The WorkFlowItem class 414 is associated with theWorkFlowContainer class 410, such that one container may be used at awork item to provide data to the user executing the unit of work definedby the work item. The relationship between the WorkFlow class 406 andthe WorkFlowItem class 414 indicates that there may be many work itemobjects associated with one executing workflow. The class architectureof FIG. 3 further illustrates that a workflow list of the WorkFlowListclass 408 is an aggregate of the workflow from the WorkFlow 414 Itemclass and workflow notifications from the WorkFlowNotification 412class.

The above object oriented architecture of FIG. 3 defines how thedifferent classes interrelate in order to implement a workflow. Each ofthe above interrelated classes 402, 404, 406, 408, 410, 412, and 414provides interfaces/methods that may be used within a workflow computerprogram to implement the workflow and actions performed at a node. Theworkflow program would be executed by the workflow server 6 (FIG. 1) inthe workflow engine 2.

Following are examples of some methods of the WorkFlowService class 402,including:

-   -   WorkFlowService( ): constructs a new workflow service, which        provides access to different workflow services in the workflow        engine 2 (FIG. 1). Each workflow service is associated with        workflow templates, executing workflows, and workflow lists of        work items for a workflow.    -   connect: provides a user name, authentication, and connection        string to use to authenticate a user to provide access to a        requested workflow service, which allows access to workflow        templates, work lists, etc.    -   connection: handle returned to a user to allow access to a        particular workflow service.    -   setDatastore: a reference to a data store including documents        and objects used by the work items in the workflows associated        with the workflow service. Thus, different workflows for a        workflow service may process documents within workflow packages        from the same data store.    -   listWorkFlows: returns a list of all workflow objects of the        WorkFlow class 406.    -   listWorkLists: returns a list of all work list objects of the        WorkFlowList class 408.    -   listWorkFlowTemplates: returns a list of all template objects of        the WorkFlowTemplate class 404.

Following are examples of some methods of the WorkFlowService class 402,including:

-   -   WorkFlowTemplate( ): constructs a workflow template object        including a defined workflow. This workflow template may be        created using the GUI panels and buildtime program described        above.    -   name: returns name of a workflow template.    -   description: returns a description of the work performed by a        workflow template.    -   modifiedTime: time the workflow template was last modified.

Following are examples of some methods of the WorkFlow class 406,including:

-   -   WorkFlow( ): constructs a workflow object representing a        workflow comprised of nodes and work items for a specified        workflow. The workflow may also be provided a container that is        used to allow users of different work items to communicate        and/or a work packet comprised of one or more documents or        objects to be processed as part of the workflow.    -   get/setName: returns or sets the name for a workflow.    -   workFlowTemplateName: returns the name of the workflow template        associated with the workflow.    -   notificationTime: returns the time of the last notification        generated for the workflow in response to a user not performing        an action for one accessed node within a specified time period.    -   modifiedTime: Returns the last time the workflow was modified.    -   stateChangeTime: returns the last time a state change occurred        with the workflow:    -   startTime: returns the time the workflow was started.    -   endTime: returns the time the workflow ended.    -   state: returns a state of the workflow, such as ready, running,        finished, terminated, suspended, terminating, suspending,        deleted, etc.    -   inContainer: returns the input container associated with the        workflow.    -   start: starts a workflow with a container if the state is ready.    -   terminate: terminates the workflow if the state is running,        suspended, or suspending.    -   suspend: suspends the workflow if the state is running.    -   resume: resumes a suspended workflow if the state is suspended        and suspending.    -   add: adds a workflow to the system that is associated with one        specified workflow template.

Following are examples of methods of the WorkFlowContainer class 410,which instantiates a container object used with a workflow to transportinformation among the nodes.

-   -   WorkFlowContainer( ): constructs a container object for a        container used within a particular workflow.    -   get/setPriority: get/sets the priority for an item in the        container.    -   get/setActivityNode: get/sets the current node being processed,        may also get/set information on the current activity node.    -   get/setWorkPacketID: get/sets an identifier of a work packet        being routed through the system.    -   get/setActionPerformed: get/sets information on an action being        performed.    -   get/setUserVariable: get/sets a variable maintained in the        container, that may have predefined values. The priority is        maintained for a user variable in the container.    -   retrieve: retrieves and refreshes the container.    -   update: updates the container data.

Following are examples of some methods of the WorkList class 408, wherea work list object is a representation of a work list in the system. Asdiscussed, a work list object comprises a collection of work items andnotifications for an executing workflow.

-   -   WorkList( ): constructs a work list object for a specified work        list. A work list consists of work items.    -   get/set ACLName: get/sets the action control list (ACL) name for        the work list including the actions that may be performed as        part of units of work for the work list.    -   listWorkItems: lists the work items on the work list.    -   listWorkItemsByTemplate: returns the work items for the work        list by the specified workflow template name.    -   listWorkItemsByNode: returns a list of the work items assigned        to each node in the work flow.    -   listProcessNotifications: lists notifications generated during        workflow that are associated with the workflow process. For        instance, the notification provides a general notification for        the workflow. In certain implementations, a notification process        is activated and performed as a background process to generate        notifications.    -   listActivityNotifications: lists notifications generated during        workflow that are associated with a particular activity, such as        a user not performing an activity within a specified time. For        instance, the notification may enable notifications for        activities at particular nodes.    -   add/update/delete/retrieve: separate commands that allow user to        add, update, delete, and retrieve a work list.

Additional commands may be provided to access the information in thework list, such as filter commands to provide filters for accessinginformation from the work list, thresholds of the number of items thatcan be in the work list, etc.

Following are examples of some methods of the WorkFlowItem class 414,where a work item object represents a unit of work performed in theworkflow. The following methods are used to create and modify workitems, and obtain information thereon.

-   -   WorkFlowItem( ): constructs a work item for a specified        workflow, node, and owner.    -   name: returns the name of the node to which the work item is        assigned.    -   state: returns a state of the work item, such as not set, ready,        running, finished, terminated, suspended, disabled, checked out,        in error, executed, etc. A work item is checked out when a user        has accessed the work item to perform the actions defined for        the work item.    -   workFlowName: returns the name of the workflow including the        work item.    -   workFlowTemplateName: returns the name of the workflow template        including the work item.    -   priority, owner, notificationTime, startTime, creationTime,        modifiedTime: methods that return information on the priority,        owner, time of last notification, time of creation and time of        last modification for a work item, respectively.    -   retrieve start, finish: methods used to retrieve, begin        executing, and complete a work item, respectively.    -   checkIn, checkOut: checkOut locks a work item to prevent other        users at a node from accessing the work item and changes the        state of the work item to checked out. Upon check out, the        container associated with the work item is accessed from the        previous node using the inContainer method. The checkIn method        receives the completed work item from the user, releases the        lock, and provides the container to route to the next node.    -   inContainer: method that obtains container from previous node        for use with work item checked out at current node being        processed.    -   outContainer: method generates an out container to include        contents of container user accessed at work item, including any        changes made by the user to the data in the container. A handle        of the out container is generated and provided with checkOut        method called for the next node to provide that container to the        user of the next node in the workflow.

Following are examples of some methods of the WorkFlowNotification class412, where a notification object represents a generated notification.The following methods are used to create and modify notifications, andobtain information thereon.

-   -   WorkFlowNotification( ): constructs a notification object having        a specified notification name, notification type, and owner name        for a specified workflow service and workflow. The notification        type indicates how the owner is notified.    -   state: returns a state of the notification, such as not set,        ready, runing, finished, terminated, suspended, disabled, etc.    -   priority owner, notificationTime, startTime, creationTime,        modifiedTime,    -   receivedTime: these methods return the priority of the        notification, owner of the notification, time that must elapse        before the notification is generated, time the notification        started, time the notification was crated, time of last        notification to the notification, time the notification was        received, respectively. The notification would be started and        executed as a background process.    -   receiveReason: returns a received reason for the notification.    -   retrieve, cancel: methods that retrieve and cancel a        notification, respectively.    -   transfer: transfers a notification to a specified user. In this        way, a notification can be transferred from the current owner to        some other user.

The above described methods and classes would be included in a workflowprogram executed by the workflow server 6 (FIG. 1) to execute theworkflow. The methods described above would be used to access and modifythe workflow related objects, such as the workflow, work items,notifications, containers, etc. when running the workflow. The abovedescribed methods may also be used in other programs that can obtaininformation and status on a workflow.

FIGS. 4–5 illustrate an example of program logic in a workflow programexecuted by the workflow server 6 (FIG. 1) utilizing the above discussedmethods to implement a workflow. With respect to FIG. 4, control beginsat block 450 where the program calls the constructor methods,WorkFlowService( ) to construct a workflow service object. The workflowprogram would then call (at block 452) the WorkFlowService list methods,such as listWorkFlows, listWorkLists, listWorkFlowTemplates, to obtaininformation on the workflows, workflow templates, and work lists for aworkflow service. This information may then be presented to a user forselection. Various other methods in the classes may be called to accessinformation on the workflow to present to the user when making adecision on which workflow to execute.

At block 454, user selection of a workflow to process is received. Theworkflow program then calls (at block 456) the WorkFlow start method tostart the workflow. The workflow program then calls (at block 458) thelistWorkItemsByNode method to obtain all the work items for the startedworkflow, and the nodes to which the one or more items are associated.The workflow program then performs a loop at blocks 460 through 490 foreach node i in the workflow, as determined from the list of work itemsby node. For each node i, the workflow program performs a loop at block462 to 488 for each work item j associated with node i. If (at block464) there is a notification for the work item and the user that is theowner of the item, as determined from the methods, then the workflowprogram retrieves (at block 466) retrieves the notification and thenstarts a monitor to determine if the time period for the notificationhas elapsed without the work item completing. From block 464 or 466, theworkflow program calls (at block 468) the checkOut method to lock thework item j. The inContainer method is called (at block 470) to accessany container associated with the work item j. Once the work item j islocked, the workflow program then executes (at block 474) the actionsassociated with the work item j.

Control then proceeds to block 476 in FIG. 5, where the workflow programcalls container get and set methods to access or modify the data andvariables in the container accessed for the work item j in response toexecuting actions assigned to that work item j. For instance, as part ofperforming actions for a work item, the user of the work item may readand write data to the container. The workflow program receives (at block482) indication from a user that the actions associated with the workitem have completed. The workflow program further calls (at block 486)the checkin method to release the lock on the work item j and theoutContainer method to generate a new container including any updates toprovide to the user at the next node in the workflow. The handle to thenew container would be used in the next called checkOut method toprovide the container to the user at the next node of the workflow. Ifthere are further work items for the node i, then control proceeds (atblock 488) back to block 452 to retrieve the next work item. Aftercompleting all the work items for node i, control proceeds (at block490) back to block 460 to process the next node in the work list.

The above described logic utilized workflow related classes and themethods therein to implement a workflow and obtain information thereon.The workflow server 6, or some other component in the workflow engine 2(FIG. 1), would then translate the workflow objects and methods intoapplication specific commands, such as Structured Query Language (SQL)commands to manipulate the data in the runtime database 4 and processtemplate 8 to obtain information on the workflow and implement workflowoperations.

Using Database Stored Procedures in the Workflow Design

FIG. 6 illustrates a workflow architecture including a client 500, suchas the workflow clients 12 a, b . . . n described with respect toFIG. 1. The client 500 is capable of invoking, in response to user inputor executing an application program, one or more workflow applicationprogramming interfaces (APIs) 502 to perform workflow related operationsand workflow metadata APIs 504 to access, update or modify workflowrelated information maintained in a database 506. The workflow APIs 502may implement the object oriented workflow classes described above, suchas those described with respect to FIG. 3. In certain implementations,the workflow APIs 502 and 504 may be implemented in a commonly usedobject oriented programming language, such as Java.

The client 500 further includes a mapping 508 of the APIs 502 and 504 tostored procedure calls that invoke stored procedures 510 a, b . . . n,512 a, b . . . n on a database server 514. Thus, for each API 502 and504, there are one or more stored procedure calls to invoke one or morestored procedures 510 a, b . . . n, 512 a, b . . . n on the databaseserver 514 to perform the action specified by the API command. Theclient stored procedure call corresponding to the called API providesinput parameters to the stored procedure 510 a, b . . . n, 512 a, b . .. n. In response to the call, the stored procedures 510 a, b . . . n,512 a, b . . . n execute within the database server 514 and mayprocesses numerous database records in the database 506 according to theinput parameters or perform a non-SQL related action, such astransmitting native workflow code to the workflow server 518 to execute.In certain stored procedure implementations, the client cannot interruptthe stored procedures during execution. The stored procedures 510 a, b .. . n, 512 a, b . . . n may comprise a block of procedural constructsand may include Structured Query Language (SQL) statements, i.e., anapplication program. Stored procedures are maintained at the databaseserver 514 for access and reuse by multiple clients 500. Further detailsof stored procedures are described in the publication “A Complete Guideto DB2 Universal Database,” “A Complete Guide to DB2 UniversalDatabase,” which was incorporated by reference above.

The database server 512 includes a database program 516 to performdatabase operations, such as execute stored procedure calls and executeSQL statements to access data in the database 506. The workflow functionstored procedures 510 a, b . . . n include the workflow engine nativecode, e.g., C, C++, etc., capable of causing a workflow server 518, suchas the workflow server 6 described with respect to FIG. 1, to performthe workflow function specified by the corresponding workflow API 502.The workflow metadata stored procedures 512 a, b . . . n include SQLstatements to access data in the database 506 and perform databaseoperations on such data.

The client 500 executing the workflow APIs 502 and 504 may comprise aseparate client machine that communicates with the database server 514over a network or other connection (not shown), or comprise a programexecuting on the database server 514. The database server 514 comprisesa separate server class machine for maintaining the stored procedures510 a, b . . . n and 512 a, b . . . n and database program 516 thatcontrols access to the database 506. The database program 516 maycomprise any database client/server program known in the art, such asIBM DB2, Oracle Corporation's ORACLE 8, Microsoft SQL Server, ** etc.**MQSeries, IBM, and DB2 are registered trademarks of InternationalBusiness Machines Corp.; Microsoft and Microsoft SQL Server aretrademarks of Microsoft Corporation; ORACLE is a trademark of the OracleCorporation; Java is a trademark of Sun Microsystems, Inc.

In Java implementations, the mapping 508 may comprise Java DatabaseConnectivity (JDBC) CallableStatements, where each CallableStatementassigns a stored procedure call in the native SQL of the databaseprogram 518 to an escape syntax, which may comprise the workflow APIs502, 504. Thus, for each API, one separate JDBC CallableStatement woulddefine a stored procedure to call to implement the workflow relatedoperation associated with the API.

FIG. 7 illustrates logic implemented in the workflow APIs 502 and 504 inthe client 500 to implement the client 500 invoked API. Upon receiving(at block 550) an API call 502, 504, the mapping 508 is processed (atblock 552) to determine one or more stored procedure calls correspondingto the received API. The client 500 then invokes (at block 554) thedetermined stored procedure call(s), including the name of the calledstored procedure and the database server 514 including the called storedprocedure, and transfers the call to the database server 514. In thedescribed implementations, the client 500 generates a stored procedureCALL statement specifying the name of the server stored procedure 510 a,b . . . n, 512 a, b . . . n and the parameters received as input by thestored procedure 510 a, b . . . n, 512 a, b . . . n.

The mapping 508 may associate multiple stored procedure calls with oneAPI call, such that invocation of the API call invokes the associatedmultiple stored procedures.

FIG. 8 illustrates logic implemented in the database program 516 toprocess the stored procedure calls from the client 500. In response toreceiving (at block 560) the stored procedure call, communicates fromthe client 500 to the database server 514, the database program 516executes (at block 562) the called stored procedure 5 10 a, b . . . n,512 a, b . . . n. If (at block 564) the received API is a workflow API502, then the corresponding called stored procedure 510 a, b . . . nincludes the workflow server 518 native code. This stored procedure 510a, b . . . n would then instruct the database program 516 to transfer(at block 566) the native code included in the called stored procedureto the workflow server 518 to execute and perform the function definedby the API 502. With the workflow function stored procedures 510 a, b .. . n the workflow server 518 native code is wrapped in the storedprocedure. Otherwise, if the stored procedure is a workflow metadatastored procedure 512 a, b . . . n including SQL statements, then thedatabase program 516 would execute (at block 570) such SQL statements toaccess workflow metadata in the database 506 and perform any specifiedSQL operations thereon. After the executed stored procedure completesall processing, status or result data may be returned to the client 502.

There are numerous ways the stored procedures may be used to access andupdate workflow metadata in the database 506 and then invoke workflowoperations on the workflow server 6. For instance, during workflowruntime, the client 500 may call workflow metadata APIs 504 to accessworkflow related information, such as worklists, access control lists,etc., and then subsequently call a workflow API 502 that specifies aworkflow function to perform in the workflow server 518 on the metadataaccessed from the database 506. Alternatively, a stored procedure 510 a,b . . . n or 512 a, b . . . n may include SQL statements to access datafrom the database 506 and then transfer such accessed metadata alongwith native code to the workflow server 518 to execute. For instance,the workflow function stored procedure 510 a, b . . . n may accessworklists, access control lists, etc., from the database 506 and thenpass such data along with native code to the workflow server 6 toprocess during workflow operations. Still further, one stored procedure510 a, b, . . . n, 512 a, b . . . n may access workflow metadata fromthe database 506 and then call and directly pass such accessed workflowmetadata to a workflow function stored procedure 510 a, b . . . n topass to the workflow server 518 to process.

Still further, a stored procedure may pass native code to the workflowserver 518 to execute and receive return workflow metadata from theworkflow server 518 to apply to the database 506. The same or anotherstored procedure on the database server 514 may then use SQL statementsto update the database 506 with the returned workflow metadata.Alternatively, the returned workflow metadata may be passed back to theclient 500, and the client 500 may further call workflow metadata APIs504 to invoke a workflow metadata stored procedure 512 a, b . . . n toupdate the database 506 with the returned workflow metadata from theworkflow server 518.

Thus, any workflow related operation comprising a combination of callsto the workflow server 518 and accesses of workflow metadata in thedatabase 506 may be combined into one stored procedure in the databaseserver 514 or distributed across multiple stored procedures.

Moreover, in certain implementations, one workflow API 502 may map tomultiple stored procedure calls. For instance, one stored procedure callauthenticates the user and provides a connection to the workflow server518 and runtime database 516, one other stored procedure performs therequested workflow related action, and yet a further stored proceduredisconnects the authenticated user.

The described implementations transform client API calls to storedprocedure calls that are executed on a separate database server toperform the function specified by the API call with respect to theworkflow server 8 and/or the database 506.

In implementations where multiple vendors provide workflow engines foruse in a federated system, each vendor may use the same API calls, butprovide a different set of stored procedure code to implement the actionspecified with the API to accommodate the differences in the vendor'sworkflow server and database structure. Thus, the workflow APIs 502, 504remain the same across vendor implementations, whereas each vendorprovides the specific stored procedure programs 510 a, b . . . n and 512a, b . . . n to perform the action associated with the APIs on thevendor specific workflow server 518 and database 506.

Additional Implementation Details

The preferred embodiments may be implemented as a method, apparatus orarticle of manufacture using standard programming and/or engineeringtechniques to produce software or code. The term “article ofmanufacture” as used herein refers to code or logic implemented in acomputer readable medium (e.g., magnetic storage medium (e.g., hard diskdrives, floppy disks, tape, etc.), optical storage (CD-ROMs, opticaldisks, etc.), volatile and non-volatile memory devices (e.g., EEPROMs,ROMs, PROMs, RAMs, DRAMs, SRAMs, firmware, programmable logic, etc.).Code in the computer readable medium is accessed and executed by aprocessor. The code in which preferred embodiments are implemented mayfurther be accessible through a transmission media or from a file serverover a network. In such cases, the article of manufacture in which thecode is implemented may comprise a transmission media, such as a networktransmission line, wireless transmission media, signals propagatingthrough space, radio waves, infrared signals, etc. Of course, thoseskilled in the art will recognize that many modifications may be made tothis configuration without departing from the scope of the presentinvention, and that the article of manufacture may comprise anyinformation bearing medium known in the art.

The workflow client and server may be implemented within any vendorworkflow program known in the art.

In the described implementations, the actions were implemented as Javamethods. Alternatively, the actions may be implemented in anyprogramming language known in the art.

In the described implementations, the class architecture is implementedas an object oriented class architecture. Alternatively, non-objectoriented programming techniques may be used to implement the describedclass architecture.

The foregoing description of the preferred embodiments of the inventionhas been presented for the purposes of illustration and description. Itis not intended to be exhaustive or to limit the invention to theprecise form disclosed. Many modifications and variations are possiblein light of the above teaching. It is intended that the scope of theinvention be limited not by this detailed description, but rather by theclaims appended hereto. The above specification, examples and dataprovide a complete description of the manufacture and use of thecomposition of the invention. Since many embodiments of the inventioncan be made without departing from the spirit and scope of theinvention, the invention resides in the claims hereinafter appended.

1. A method for performing workflow related operations, comprising:receiving an application programming interface (API) call to perform aworkflow related operation; determining at least one stored procedurecall associated with the received API call; and calling the determinedat least one stored procedure call, wherein each stored procedure callcauses the execution of one determined stored procedure on a databaseserver to perform the workflow related operation of an API of thereceived API call; wherein the received API call comprises a first callto a first stored procedure associated with a first API call, whereinthe first stored procedure includes native workflow server code, whereinexecuting the first stored procedure comprises communicating the nativeworkflow server code to a workflow server to perform the workflowrelated operation associated with a first API of the first API call,wherein the workflow server returns workflow metadata, furthercomprising: receiving a second stored procedure call associated with asecond API call that invokes a second stored procedure on the databaseserver, wherein the second stored procedure includes databasestatements; and executing the second stored procedure to cause adatabase program to execute the database statements to update a workflowdatabase with the returned workflow metadata.
 2. The method of claim 1,wherein at least one stored procedure call invokes one stored procedurein the database server that includes native workflow server code tocommunicate to a workflow server to execute to perform the workflowrelated operation of the API and wherein at least one stored procedurecall invokes one stored procedure in the database server that includesdatabase statements executed by a database program to access workflowrelated metadata for the API.
 3. The method of claim 1, wherein theworkflow related operation for at least one API is to be performed on aworkflow server and wherein the workflow related operation for at leastone API is to access workflow metadata from a workflow database.
 4. Themethod of claim 1, wherein the workflow related operation comprises afunction to perform on a workflow server, wherein the database serverincludes a database program that executes one determined storedprocedure to perform: communicating native workflow server code includedin the executed stored procedure to the workflow server, wherein theworkflow server executes the native workflow server code to perform theworkflow related operation of the API.
 5. The method of claim 4, whereinthe API and native workflow server code are in different programminglanguages.
 6. The method of claim 1, wherein the workflow relatedoperation concerns accessing workflow metadata in a workflow database,wherein the database server includes a database program that executesone determined stored procedure to perform: executing databasestatements included in the executed stored procedure to access workflowmetadata in the workflow database.
 7. The method claim 3, wherein thedatabase statements comprise Structured Query Language (SQL) statements.8. A method for performing workflow related operations at a databaseserver in communication with a client, comprising: receiving at leastone call to one stored procedure at the database server associated withan application programming interface (API) call invoked from the clientto perform a workflow related operation; and executing, at the databaseserver, the at least one called stored procedure to perform the workflowrelated operation of an API of the API call; wherein the received atleast one call to one stored procedure comprises a first call to a firststored procedure associated with a first API call, wherein the firststored procedure includes native workflow server code, wherein executingthe first stored procedure comprises communicating the native workflowserver code to a workflow server to perform the workflow relatedoperation associated with a first API of the first API call, wherein theworkflow server returns workflow metadata, further comprising: receivinga second stored procedure call associated with a second API call thatinvokes a second stored procedure on the database server, wherein thesecond stored procedure includes database statements; and executing thesecond stored procedure to cause a database program to execute thedatabase statements to update a workflow database with the returnedworkflow metadata.
 9. The method of claim 8, wherein the received atleast one call to one stored procedure comprises third and fourth storedprocedure calls to third and fourth stored procedures, respectively, onthe database server to implement the workflow related operation of theAPI.
 10. The method of claim 9, wherein executing the third storedprocedure comprises authenticating the client and establishing aconnection and wherein executing the fourth stored procedure comprisesperforming the workflow related operation of the API.
 11. The method ofclaim 9, wherein executing the third stored procedure comprisesaccessing workflow metadata from a workflow database and whereinexecuting the fourth stored procedure comprises communicating nativeworkflow server code and the accessed workflow metadata to a workflowserver, wherein the workflow server processes the communicated nativeworkflow server code and the workflow metadata to perform the workflowrelated operation of the API.
 12. The method of claim 9, whereinexecuting the third stored procedure comprises communicating nativeworkflow server code to a workflow server, wherein the workflow serverprocesses the communicated native workflow server code to perform theworkflow related operation of the API and returns workflow metadata, andwherein executing the fourth stored procedure call for the API comprisesupdating a workflow database with the workflow metadata returned by theworkflow server.
 13. The method of claim 8, wherein the received atleast one call to the stored procedure comprises a third call to a thirdstored procedure associated with a third API call, wherein the thirdstored procedure includes database statements, wherein executing thethird stored procedure comprises communicating the database statementsto a database program to access workflow metadata from a workflowdatabase, further comprising: receiving a fourth stored procedure callassociated with a fourth API call that invokes a fourth stored procedureon the database server, wherein the fourth stored procedure includesnative workflow server code; and executing the fourth stored procedureto communicate the native workflow server code and the accessed workflowmetadata included therein to a workflow server to perform the workflowrelated operation associated with a fourth API of the fourth API call.14. The method of claim 13, wherein the third stored procedure returnsthe accessed workflow metadata to the client, and wherein the fourthstored procedure call from the client passes the accessed workflowmetadata to the fourth stored procedure to communicate to the workflowserver with the native workflow server code.
 15. The method of claim 14,wherein the third stored procedure returns the returned workflowmetadata from the workflow server to the client, and wherein the fourthstored procedure call from the client passes the returned workflowmetadata from the workflow server to the fourth stored procedure to callthe database program to update the workflow database with the returnedworkflow metadata.
 16. A system for performing workflow relatedoperations, comprising: a database server; a tangible computer readablemedium including a plurality of stored procedures, wherein each storedprocedure is associated with at least one application programminginterface (API) call defined to perform a workflow related operation,wherein the computer readable medium is accessible to the databaseserver; a workflow server coupled to the database server; means forreceiving one API call to perform one workflow related operation; meansfor determining at least one stored procedure call associated with thereceived API call; means for calling the determined at least one storedprocedure call; and means, performed by the database server, forexecuting at least one stored procedure in response to the determined atleast one stored procedure call being called to perform the workflowrelated operation of an API of the API call; wherein the received APIcall comprises a first call to a first stored procedure associated witha first API call, wherein the first stored procedure includes nativeworkflow server code, wherein executing the first stored procedurecomprises communicating the native workflow server code to the workflowserver to perform the workflow related operation associated with a firstAPI of the first API call, wherein the workflow server returns workflowmetadata, further comprising: means for receiving a second storedprocedure call associated with a second API call that invokes a secondstored procedure on the database server, wherein the second storedprocedure includes database statements; and means for executing thesecond stored procedure to cause a database program to execute thedatabase statements to update a workflow database with the returnedworkflow metadata.
 17. The system of claim 16, wherein at least onestored procedure call invokes one stored procedure that includes nativeworkflow server code to perform the workflow related operation of theAPI, and wherein at least one stored procedure call invokes one storedprocedure that includes database statements to access workflow relatedmetadata for the API, further comprising: a database; means, performedby the workflow server, for receiving native workflow server code fromone stored procedure; means, performed by the workflow server, forexecuting the received native workflow server code to perform theworkflow related operation; and means for executing database statementsfrom one stored procedure to access workflow related metadata for theAPI from the database.
 18. The system of claim 16, wherein the workflowrelated operation for at least one API is to be performed on a workflowserver and wherein the workflow related operation for at least one APIis to access workflow metadata from a workflow database.
 19. The systemof claim 16, further comprising: a workflow server, wherein the workflowrelated operation comprises a function to perform on the workflowserver; means, performed at the database server, for executing onedetermined stored procedure to communicate native workflow server codeincluded in the executed stored procedure to the workflow server; andmeans, performed by the workflow server, for executing the nativeworkflow server code to perform the workflow related operation of theAPI.
 20. The system of claim 19, wherein the API and native workflowserver code are in different programming languages.
 21. The system ofclaim 16, further comprising: a workflow database, wherein the workflowrelated operation concerns accessing workflow metadata in the workflowdatabase; and means, performed at the database server, for executing thedatabase statements in the determined stored procedure to accessworkflow metadata in the workflow database.
 22. The system claim 17,wherein the database statements comprise Structured Query Language (SQL)statements.
 23. A system for performing workflow related operations,comprising: a database server; a client in communication with thedatabase server; means, performed by the client, for executing anapplication programming interface (API) call to perform a workflowrelated operation, wherein at least one stored procedure call at thedatabase server is associated with the executed API call; means,performed by the client, for communicating the at least one storedprocedure call to at least one stored procedure associated with theexecuted API call to the database server; and means, performed by thedatabase server, for executing the at least one called stored procedureto perform the workflow related operation of an API of the API call;wherein the at least one stored procedure call comprises a first andsecond stored procedure calls to first and second stored procedures,respectively, on the database server to implement the workflow relatedoperation of the API and further comprising: a workflow database,wherein the means for executing the at least one called stored procedureat the database server executes the first stored procedure to accessworkflow metadata from the workflow database; a workflow server, whereinthe means for executing the at least one called stored procedure at thedatabase server executes the second stored procedure at the databaseserver to communicate native workflow server code and the accessedworkflow metadata to the workflow server; and means performed by theworkflow server for processing the communicated native workflow servercode and the workflow metadata to perform the workflow related operationof the API.
 24. The system of claim 23, wherein the means for executingthe at least one called stored procedure performs executing a thirdstored procedure to authenticate the client and establish a connectionand wherein executing a fourth stored procedure call comprisesperforming the workflow related operation of the API.
 25. The system ofclaim 23, further comprising: wherein the means for executing the atleast one called stored procedure at the database server executes athird stored procedure to communicate native workflow server code to theworkflow server; means, performed by the workflow server, for processingthe communicated native workflow server code to perform the workflowrelated operation of the API and returning workflow metadata; andwherein the means for executing the at least one called stored procedureexecutes a fourth stored procedure call for the API updates the workflowdatabase with the workflow metadata returned by the workflow server. 26.The system of claim 23, wherein a third stored procedure is associatedwith a third API call and includes database statements, furthercomprising: the workflow database in communication with the databaseserver; means, performed by the database server, for accessing accessworkflow metadata from the workflow database in response to executingthe third stored procedure; means, performed by the database server, forreceiving a fourth stored procedure call associated with a second APIcall; wherein the means, performed by the database server, for executingthe at least one stored procedure performs: (i) executing the fourthstored procedure including native workflow server code; and (ii)executing the fourth stored procedure to communicate the native workflowserver code and the accessed workflow metadata included therein to theworkflow server; and means, performed by the workflow server, forexecuting the native workflow server code communicated from the databaseserver to process the workflow metadata received from the databaseserver to perform the workflow related operation associated with afourth API of the fourth API call.
 27. The system of claim 26, whereinthe means for executing the at least one stored procedure furtherperforms executing the third stored procedure to return the accessedworkflow metadata to the client; and means, performed by the client, forpassing the accessed workflow metadata received from the database serverwith the fourth stored procedure call to the database server tocommunicate to the workflow server with the native workflow server code.28. The system of claim 23, wherein the received call to the storedprocedure comprises a third call to a first stored procedure associatedwith a third API call, wherein the third stored procedure includesnative workflow server code, further comprising: wherein the means forexecuting the at least one stored procedure performs executing the thirdstored procedure to communicate the native workflow server code in thethird stored procedure to the workflow server to process and perform theworkflow related operation associated with a third API of the third APIcall; means for returning, performed by the workflow server, workflowmetadata, wherein the means for executing the at least one storedprocedure further performs receiving a fourth stored procedure callassociated with a fourth API call that invokes the fourth storedprocedure on the database server, wherein the fourth stored procedureincludes database statements; and executing, at the database server, thedatabase statements in the fourth stored procedure to update theworkflow database with the returned workflow metadata.
 29. The system ofclaim 23, wherein a third stored procedure returns the returned workflowmetadata from the workflow server to the client, and wherein the fourthstored procedure call from the client passes the returned workflowmetadata from the workflow server to the fourth stored procedure to callthe database program to update the workflow database with the returnedworkflow metadata.
 30. An article of manufacture including code forperforming workflow related operations by: receiving an applicationprogramming interface (API) call to perform a workflow relatedoperation; determining at least one stored procedure call associatedwith the received API call; and calling the determined at least onestored procedure call, wherein each stored procedure call causes theexecution of one determined stored procedure on a database server toperform the workflow related operation of an API of the API call;wherein the received at least one stored procedure call comprises afirst and second stored procedure calls to first and second storedprocedures, respectively, on the database server to implement theworkflow related operation of the API and further comprising: executingthe at least one called stored procedure at the database server executesthe first stored procedure to access workflow metadata from a workflowdatabase; executing the at least one called stored procedure at thedatabase server executes the second stored procedure at the databaseserver to communicate native workflow server code and the accessedworkflow metadata to a workflow server; and processing the communicatednative workflow server code and the workflow metadata to perform theworkflow related operation of the API at the workflow server.
 31. Thearticle of manufacture of claim 30, wherein at least one storedprocedure call invokes one stored procedure in the database server thatincludes native workflow server code to communicate to a workflow serverto execute to perform the workflow related operation of the API andwherein at least one stored procedure call invokes one stored procedurein the database server that includes database statements executed by adatabase program to access workflow related metadata for the API. 32.The article of manufacture of claim 30, wherein the workflow relatedoperation for at least one API is to be performed on a workflow serverand wherein the workflow related operation for at least one API is toaccess workflow metadata from a workflow database.
 33. The article ofmanufacture of claim 30, wherein the workflow related operationcomprises a function to perform on a workflow server, wherein thedatabase server includes a database program that executes one determinedstored procedure to perform: communicating native workflow server codeincluded in the executed stored procedure to the workflow server,wherein the workflow server executes the native workflow server code toperform the workflow related operation of the API.
 34. The article ofmanufacture of claim 33, wherein the API and native workflow server codeare in different programming languages.
 35. The article of manufactureof claim 30, wherein the workflow related operation concerns accessingworkflow metadata in a workflow database, wherein the database serverincludes a database program that executes one determined storedprocedure to perform: executing database statements included in theexecuted stored procedure to access workflow metadata in the workflowdatabase.
 36. The article of manufacture of claim 34, wherein thedatabase statements comprise Structured Query Language (SQL) statements.37. An article of manufacture including code for performing workflowrelated operations at a database server in communication with a clientby: receiving at least one call to one stored procedure at the databaseserver associated with an application programming interface (API) callinvoked from the client to perform a workflow related operation; andexecuting, at the database server, the at least one called storedprocedure to perform the workflow related operation of an API of the APIcall; wherein the at least one received call to the stored procedurecomprises a first call to a first stored procedure associated with afirst API call, wherein the first stored procedure includes nativeworkflow server code, wherein executing the first stored procedurecomprises communicating the native workflow server code to a workflowserver to perform the workflow related operation associated with a firstAPI of the first API call, wherein the workflow server returns workflowmetadata, further comprising: receiving a second stored procedure callassociated with a second API call that invokes a second stored procedureon the database server, wherein the second stored procedure includesdatabase statements; executing the second stored procedure to cause adatabase program to execute the database statements to update a workflowdatabase with the returned workflow metadata.
 38. The article ofmanufacture of claim 37, wherein the received at least one call to onestored procedure comprises a third and fourth stored procedure calls tothird and fourth stored procedures, respectively, on the database serverto implement the workflow related operation of the API.
 39. The articleof manufacture of claim 38, wherein executing the third stored procedurecomprises authenticating the client and establishing a connection andwherein executing the fourth received stored procedure call comprisesperforming the workflow related operation of the API.
 40. The article ofmanufacture of claim 38, wherein executing the third stored procedurecomprises accessing workflow metadata from a workflow database andwherein executing the fourth stored procedure comprises communicatingnative workflow server code and the accessed workflow metadata to aworkflow server, wherein the workflow server processes the communicatednative workflow server code and the workflow metadata to perform theworkflow related operation of the API.
 41. The article of manufacture ofclaim 38, wherein executing the third stored procedure comprisescommunicating native workflow server code to a workflow server, whereinthe workflow server processes the communicated native workflow servercode to perform the workflow related operation of the API and returnsworkflow metadata, and wherein executing the fourth stored procedurecall for the API comprises updates a workflow database with the workflowmetadata returned by the workflow server.
 42. The article of manufactureof claim 37, wherein the at least one received call to the storedprocedure comprises a third call to a third stored procedure associatedwith a third API call, wherein the third stored procedure includesdatabase statements, wherein executing the third stored procedurecomprises communicating the database statements to a database program toaccess workflow metadata from a workflow database, further comprising:receiving a fourth stored procedure call associated with a fourth APIcall that invokes a fourth stored procedure on the database server,wherein the fourth stored procedure includes native workflow servercode; and executing the fourth stored procedure to communicate thenative workflow server code and the accessed workflow metadata includedtherein to a workflow server to perform the workflow related operationassociated with a fourth API of the fourth API call.
 43. The article ofmanufacture of claim 42, wherein the third stored procedure returns theaccessed workflow metadata to the client, and wherein the fourth storedprocedure call from the client passes the accessed workflow metadata tothe fourth stored procedure to communicate to the workflow server withthe native workflow server code.
 44. The article of manufacture of claim37, wherein the third stored procedure returns the returned workflowmetadata from the workflow server to the client, and wherein the fourthstored procedure call from the client passes the returned workflowmetadata from the workflow server to the fourth stored procedure to callthe database program to update the workflow database with the returnedworkflow metadata.